Following Poachers That Illegally Capture the Nation's Rare Songbirds.

The activist's gaze sweeps over vast expanses of open meadows, searching for suspicious activity in the inky blackness.

He speaks in a muted voice as they attempt to locate a place of cover in the open area. Behind us, the huge urban center of Beijing slumbers on. During the vigil, the only sound is our own breath.

Suddenly, as the sky begins to brighten with the approaching day, there is the crunch of footsteps. The hunters have arrived.

Caught

In the skies above us, a multitude of winged travelers, many so small that they could rest in the cup of a hand, are traveling to the south for winter.

They have utilized the warmer months in Siberia, or Mongolia, eating bugs and berries. As the year winds down and icy winds bring the first frosts of winter, they journey to southern locales to find food and shelter.

The nation hosts over 1500 bird species, accounting for thirteen percent of the world's total – more than 800 of those are migratory birds. Several of the major migration routes they follow converge in China.

The area of meadow being monitored, on the edges of the Chinese capital, is an haven for small birds – any further and the urban landscape offer little opportunity to rest among towering rows of concrete.

It is equally attractive for the poachers and their "mist nets", so fine you can hardly spot them.

The one we nearly walked into was extending over half the length of the field and held up with bamboo poles. At its center, a tiny bird was fighting hard to untangle itself, but the more it moved, the more its feet got ensnared.

This was a meadow pipit, a protected bird in China, and an important "indicator species" – meaning if its population is healthy, so is its habitat.

Tracking the Trappers

This activist, performs this duty for free using his personal funds. He has given up on many nights of sleep to release trapped birds, and he has spent the last 10 years convincing the police in Beijing to take this crime seriously.

"Back in 2015, no-one cared," he says.

So he recruited volunteers who were concerned and established a group called the Bird Protection Unit. He held public meetings and brought in the officials of the local police and forestry bureau. These consistent and determined acts of advocacy seem to have paid off. The police found that catching poachers also helped in uncovering other kinds of illegal operations.

"It became clear our goals were somewhat shared," Silva says, while pointing out that enforcement is still patchy.

His passion for avian life began during childhood. He was raised in the 1990s in a very different Beijing.

He remembers exploring the fields on the city's edges where he discovered birds, frogs and snakes. "However, beginning in the 2000s, the transformation was dramatic."

Rapid economic growth brought a huge influx of rural workers to cities. This rapid urbanisation meant grasslands were seen as empty places to build, not protected zones to preserve.

This shift shocked him. The grasslands receded, as did the ecosystems they sustained.

"I made the choice back then to work in conservation and I took this path," he says.

This has not made for an easy life. A major Beijing's biggest bird dealers found out he was under scrutiny by Silva and retaliated.

"He assembled several of his accomplices who confronted me and beat me up," Silva remembers. He says he reported to the police but those responsible were not brought to justice.

He has also lost his team of helpers over the years. This work demands covert operations and lost sleep. Silva says not many are willing to take on the difficult – and sometimes dangerous job.

"This is my full-time commitment," he says. "I made it a project because if you want to solve this big problem, you must give it your all. You cannot be half-hearted."

He says donations pays for some of the costs – more than 100,000 yuan a year – but support has waned because of the slowing economy.

So he has developed new ways to hunt the hunters.

He examines aerial photos to find the routes worn away by the poachers. He charts these against the birds' migratory routes and looks for areas where they may rest. The satellite images can even show lines of net traps which can capture hundreds of small birds during darkness.

"Siberian rubythroats and bluethroats sell for a high price," Silva says. "In urban centers like Beijing and Tianjin, those who want to own songbirds are now quite wealthy."

Although there are wildlife laws in place, Silva believes the fines to deter the activity do not outweigh the potential profits of trapping and trading songbirds.

Keeping a caged bird was – and for some generations in China, still is – a status symbol. This dates back to the Qing dynasty. Nobles and elites would build ornate bamboo cages to display their birds.

This custom that continues mainly among older individuals in their 60s or 70s. Silva says older Chinese people may not understand they are breaking the law, or understand that so many more birds were killed in a trap for them to purchase a caged bird.

"These individuals often lacked enough to eat in their youth. Now with some disposable income, they have inherited the habit and custom of caging birds," he says. "China developed so fast, there was little opportunity to raise awareness about ecology. Once people's attitudes are formed, they're extremely difficult to change."

Disrupted

Along a riverside path in Beijing, a vendor has several tiny enclosures with tiny twittering birds.

A separate individual stands outside a nearby market holding a bird cage shrouded in a black veil. He tells passers-by quietly that his songbird is rare, worth about 1900 yuan.

This offers a view of an old Beijing where informal vendors have established a niche trade.

The area by the river extends over several miles and on a typical day, there were shoppers browsing everything from old trinkets to false teeth.

We were told that wild songbirds could be bought in a small park. The location was not concealed.

Music was blasting from a speaker in a shaded area where a group of elderly ladies were choreographing a fan dance. Close by several men, all over 50, had gathered with bird cages – some had multiple in their hands. Most were covered in dark cloth.

But on this occasion there would be no sales because the police had arrived. They were interviewing the bird owners and recording details. Defiant, one man claimed he was {taking his caged bird for a walk|simply exercising his